The present invention relates to a portable lighting device with a colored lens. More particularly, the present invention relates to a portable lighting device with a mechanically selectable colored lens providing focused filtered LED light.
Portable lighting devices, such as flashlights, are common. A typical flashlight includes one or more batteries arranged within a cylindrical battery compartment that forms the handle of the light. A front end, or head, typically houses a bulb or lamp. A switch mechanism, generally placed between the lamp and the batteries, controls the flow of electricity between the batteries and the lamp. Current portable lighting devices are offered in a multitude of shapes and sizes and provide many options for a variety of disciplines including but not limited to: military; fire fighting; police; industry; camping; boating; outdoor sports; scuba; hunting; and general household use.
The need for a focused high powered beam of colored filtered light is common among hunters, astronomers, and military and security personnel engaged in various operations. It is desirable in these applications for the filter mechanism to be simple to operate so as not to interfere with the task at hand. Also, colored filtered light is preferable to white light in many of these applications in that it helps preserve the night vision of the user and nearby individuals. Additionally, filtered light may be more difficult to detect by observers. High powered light emitting diodes (LEDs) may be preferable in these applications as they consume less power than conventional incandescent bulbs, therefore lasting hundreds of hours on a set of conventional batteries, as compared to a few dozen hours for incandescent bulbs. Additionally, LED flashlights are often electronically regulated to maintain a constant light output as batteries fade. By contrast, a standard flashlight using normal light bulbs emits a progressively dimmer output, sometimes spending much of the total running time below optimum brightness level.
One way of providing colored filtered light is to provide translucent lenses in various colors that the user may insert in place of a transparent bulb cover. However, changing the filter color of the light requires disassembly and reassembly. This may be difficult to accomplish in the dark, and may be a slow, time-consuming process. Also, disassembly increases the chances of dropping and possibly losing critical parts during the exchange process. Having loose parts necessitates storage when the light is not in use.
Another approach to providing colored filtered light is to use independent lamps or bulbs, each of a different color or with a separate color filter. However, the use of multiple bulbs increases the number of component parts and raises the cost of manufacturing. Additionally, the control of multiple light sources may require more user inputs, or more complex electronic switching to take advantage of the separate bulbs.
Yet another approach to providing a variable color light source is to use a single lamp, or bulb, and a wheel fitted with a variety of colored filters. The color wheel may be fitted over the lamp and rotated to provide colored filtered light. However, in this instance, the filtered light does not pass through a lens to provide a focused beam of light.
Therefore, there is a need for a portable lighting device to emit a beam of colored filtered light that is simple to operate and easily changeable by the user. There is also a need for a portable lighting device that can provide a focused beam of light at the output of a colored filter. There is still another need for a portable lighting device that can provide a high powered focused beam of light at the output of a colored filter.